– Leonardo liked to put down his notes in mirror writing
– An average human weighs 220 A5 notebooks
– “beer nails” are metal fittings at books and notebooks which get applied to prevent that the book gets in contact with spilled beer for example (The nails provide a few millimetres of distance to the table top)
– No piece of paper can be folded more than seven times in the middle, no matter how big or thin the paper is
– The revolutionary invention of “printing with movable letters” by Johannes Guttenberg was initially invented by Bi Sheng in 1040 in China. Hence 400 years before Gutenberg
– The English sentence “The Quick Brown Fox Jumps Over The Lazy Dog« contains all 26 letters of the alphabet
– the chance to get hit by a crashing airplane while writing into a notebook is at 1:7 trillion.